Volume No. 3 Issue No.: 3 Page No.: 671-676 Jan-Mar 2009




R.M. Jayabalakrishnan*, S.Mahimairaja and C.Udayasoorian

Department of Environmental Science, Tamil Nadu Agricultural University, Coimbatore (INDIA)


Received on : October 26, 2008




The removal of pollutants from wastewater effluents by adsorption is being adopted as tertiary treatment where activated carbon is used for adsorbing the pollutants, however its use is limited by its high cost. Therefore, an attempt has been made to assess vermiculite, a phyllosilicate mineral group with high cation exchange capacity, as an alternative for activated carbon. In this investigation, the adsorption potential of raw vermiculite grade 2 was evaluated using vermiculite clay mineral barrier system for reducing pollutant loads in specially designed treatment system, where the important parameters like flow rate, effluent loading rate required were optimized.
The VCMB treatment system has reduced the Cr in the outlet end soil layer by 66.1 per cent than the inlet end soil layer. The build up of Cr in the middle vermiculite was 6.1 times more than the inlet end soil which could be attributed to its adsorption and retention properties. With reference to Na, the vermiculite treatment layer retained 12.7 times more than the top surface soil and 4.29 times as that of the inlet end soil layer. These results confirm that for the removal of Cr, salts and Na from chrome tannery effluent, the VCMB treatment system could be viable option. But in case of sulphate, it was found that its accumulation was the highest in the inlet end soil layer and was 4.24 times lower in the middle vermiculite layer which could be due to the lower anion exchange capacity of vermiculite compared with soil layer.


Keywords : Vermiculite , Treatment System, Tannery effluent, Mustard Crop.